Web registering system for multi-unit presses



Oct. 25, 1966 w. F. HUCK 3,280,737

WEB REGISTERING SYSTEM FOR MULTI-UNIT PRESSES Filed June L3, 1963 4Sheets-Sheet l INVENTOR.

WILLIAM HUC BY T TOR NE y WEB REGISTERING SYSTEM FOR MULTI-UNIT PRESSESFiled June 13, 1965 W. F. HUCK Oct. 25, 1966 4 Sheets$heet 2 NJ 3 3. O2r we W NE vfl \31 d m 21 8. A: w: p

m 08 Ag 2 km: @725 30m 205 a w:

0 mm wn INVENTOR. WILLIAM F. HUC

OR NE Y Oct. 25, 1966 w. F. HUCK 3,280,737

WEB REGISTERING SYSTEM FOR MUL'II'UNIT PRESSES Filed June 13, 1965 4Sheets-Sheet 5 INVENTOR.

58b WILLIAM F. HUCK BYQ ML. M

TTORNE Y Oct. 25, 1966 w. F. HUCK 3,280,737

WEB REGISTERING SYSTEM FOR MULTI"UNIT PRESSES Filed June L3, 1963 4Sheets-Sheet 4 INVENTOR. W l LLIAM F. H UC K ORNEY United States Patent3,280,737 WEB REGISTERING SYSTEM FOR MULTI-UNIT PRESSES William F. Huck,81 Greenway Terrace, Forest Hills, N.Y. Filed June 13, 1963, Ser. No.287,622 18 Claims. (Cl. 101181) This invention relates to web processingmachines and more particularly to apparatus for controlling the registerof the web on a multi-unit web processing machine such, for example, asa multi-color rotary gravure printing press.

It is of course important to the proper operation of such machines thatthe printing or other action of each unit take place at locations on theweb kept accurately in register with the locations acted upon by everyother unit. Off-register printing operations and problems of maintainingrequired conditions of register are, however, continuing causes ofwastes of printed matter and of delays and limitations upon productionspeeds in the operation of web processing machines. This is especiallythe case in respect to machines, such as multi-color gravure printingpresses, by which a plurality of operations are required to be performedin register on a running web at widely spaced stations of each machine.

Although it is theoretically possible to adjust several processing unitsso that the operations they perform will be in register, in practiceregister errors occur as a result of one or more of a variety ofvariable factors. Variations of the thickness, the moisture content, thetemperature or the strength of the paper or other web material beingprocessed tend to produce register errors. So also will variations ofpress room atmospheric conditions, press operating speeds, web tensionand other conditions affecting the web on the machine or the dimensionsor constancy of action of the web engaging rotary units of the machine.

It is known that register errors may be corrected by selectively varyingthe effective length of the web between a processing unit where aregister error has been detested and the preceding unit. This lengthvariation may be accomplished by displacing or by varying the speed of aroller or a web propelling couple acting upon the web travelling to thefarther unit. Where the processing units positively grip and propel theweb, as do the cylinders at each printing station of a multi-colorgravure printing press, the length of the web passing between units maybe varied by varying the rotational speed of one set of cylindersrelative to that of another set. In the use of such techniques, thetension or stretch of the web travelling between the two processingunits is varied, to the end that the web will gradually move back intoregister with the unit where register is lacking.

It will be understood that the rapidity of the register correction insuch cases depends upon the magnitude of the change of the effective weblength between the two units and the distance and the steps of frictionand tension increase in the web path between the units, as well as theweb speed. A flexible web, such as of paper, exhibits qualities of anelastic band as it is passed through the press. If it is out of registerat one unit by a few thousandths of an inch and there is a largedistance occupied by many web contacting elements between units, as inthe case of a multi-color gravure press where the web after eachimpression may pass through a drying and cooling system, etc., so as totravel a distance of 30 ft. or more between printing units, an effectivelength change of a few thousandths of an inch in .the web either willnot correct the register error or will require too long a time to do so.

3,280,737 Patented Oct. 25, 1966 For this reason, it is necessary tointroduce a substantially greater change in the effective web lengthbetween the units, which causes over-correction after a period ofcontinued web travel and thus necessitates further action to remedy theovercorrection. In practice, therefore, the correction devices operatewith continual hunting back and forth, alternately increasing anddecreasing web tension and thus keeping the web hovering close to therequired registered position.

The longer or the more obstructed is the web path between the successivecontrol points or processing units, the greater is the elastic play ofthe intervening web length and the larger the amount of correction andovercorrection required for a given register error.

It will also be evident that varying the web length between twoprocessing units in order to correct a register error at the fartherunit tends to disturb the register of the web at the near unit and, to alesser extent, at all preceding units, since the tension eifects of weblength varation at one location in the machine tend to pass through theentire machine. This problem is of course aggravated when the correctionof a small error requires a comparatively large change in the effectiveweb length.

It is an object of the present invention to provide in a multi-unit webprocessing machine a system of apparatus which will quickly andpositively correct detected errors in the register of the web.

A further object of the invention is to provide a multiunrt webprocessing machine by which a web imprinted or otherwise processed atone unit may be kept in register with the succeeding unit or unitswithout hunting.

Another object is to provide in such a machine apparatus which willcorrect detected errors in register of the web to one processing unitwithout disturbing the register of the web to other processing units.

A further object is to provide a register correction system or apparatusof the above character which will hold the register of the web at anyspeed of operation of the machine or while the machine is beingaccelerated or decelerated.

Another object is to provide in such a machine apparatus which will holdthe register of the web to the various processing units during stoppageof the machine.

Still another object is to provide such apparatus whereby coactingcylinders at the processing units will continue to be in register withthe web when they are reengaged after being separated for slow rotationduring stoppage periods.

A further object is to provide a system of apparatus of the characterabove mentioned which will serve effectively for controlling the tensionof the web travelling to a processing unit when the web moving theretois unprinted or otherwise unmarked and, therefore, no registering of theweb thereto is required.

A further object is to provide, in a web processing machine where theweb passing from one processing unit to the next is guided over a seriesof idler or free running rollers, such as oven rollers, cooling rollersor the like, engaged and driven by the web, apparatus which will actupon abrupt stoppage of the machine to free these rollers fromconstraint by the web, and thereby prevent these rollers from damagingthe web.

It is a still further object of the invention to provide a registercontrol system of the type mentioned which will serve effectively forregistering a web that is inverted by being passed over turn barsbetween successive processing units and that has a relatively highand/or an irregular tension level built up in it when it reaches or asit passes over the turn bars.

According to one aspect of the present invention, the web travellingthrough an extended path between successive processing units isdrivingly engaged by driven roller means disposed at a point in the webpath ahead of, and preferably immediately adjacent to, the farther orsecond of the two units, and upon the detection of a register error atthe second unit these roller means are acted upon so as to varytransiently the speed of the portion of the web enaged by them relativeto the speed of the portion of the web engaged by the second processingunit and thereby to vary the stretch of the web lead extending from theroller means to the second unit in the sense to correct the registererror. This transient variation of the relative speeds of the webportions is effected most advantageously by simultaneously displacingand varying the rotational speed of the roller means, so that a dualcorrective effect is obtained in said web lead, although eitherdisplacement or a rotational speed variation will give the transientvariation to some extent. Acting in cooperation with the driven rollermeans is a floating roller which is yieldably biased against the weblead approaching the driven roller means so that the tension and therebythe stretch of the web lead between the first unit and the driven rollermeans is maintained substantially constant irrespective of the registercorrecting action of the latter. In this manner, detected registererrors at the second unit are quickly and positively corrected withoutobjectionable hunting of the register control devices and withoutdisturbing the register of the web to the first unit.

According to another aspect of the invention, the proccessing units eachcomprise coacting cylinders which cyclically imprint the web and areseparable during stoppage periods of the machine to free the web, or tobe kept in slow rotation without acting upon the web; and the rollermeans comprise driven rollers engaging the web in non-slipping relationthereto so that when the cylinders are separated during stoppage of themachine the driven rollers will continue to hold the web in placerelative to the printing position of the cylinders. Since the drivenrollers are driven in synchronism with the processing cylinders from acommon rotary power source, a clutch is provided in the driving train tothe driven rollers so that these rollers may be disconnected from thepower source, and yet the cylinders kept connected with it, when theprocessing cylinders are separated.

According to another aspect of the invention, means are provided whichact upon stoppage of the machine to latch the floating tension controlroller in the working position which it then occupies so that it will beprevented from displacing the web when the web becomes slack due toseparation of the cylinders of the processing unit preceding thefloating roller, whereby to maintain the established register betweenthe web and this preceding unit.

According to yet another aspect of the invention, means are providedwhich act upon stoppage of the press to clamp the web firmly at spacedlocations therealong so that inequalities of web tension which may existalong the various leads of the web when the machine is stopped will beprevented from causing rotation of the driven rollers when the latterare declutched from the machine drive.

According to another aspect of the invention, which is important forinstallations where the web is guided over a series of rollers, such asoven rollers, cooling rollers, or the like, while passing from oneprocessing unit to the next such unit, the web guiding rollers areconstituted as idler or free running rollers and means are providedwhich act upon a sudden or emergency stoppage of the machine to cut ofior at least substantially reduce the biasing force on the floatingtension roller, whereby to reduce the web tension so that the idlerrollers are freed from constraint by the web and allowed to coast or runfreely to a stop without causing damage to the web by their continuingmomentum.

According to a further aspect of the invention, means are provided whichact to stop the processing cylinders at the same angular position eachtime a signal to stop the machine is given, so that after being rotatedslowly during a period of press stoppage the cylinders are halted at thesame angular positions they occupied when the machine was initiallystopped. Thus, when they are reengaged with the web they will continueto be in register with it.

Where Web being pocessed is inverted between processing units, as bypassing it over turn bars, and a relatively high and/ or irregulartension level is likely to build up in the web ahead of the turn bars,the invention may be applied advantageously by providing a device aheadof the turn bars to maintain substantially constant tension in the webentering the turn bars and arranging the driven register control rollersbeyond the turn bars to act upon a portion of the web leaving them. Anyof several possible arrangements of apparatus set forth herein may beutilized to achieve the purposes of the invention under theseconditions.

According to yet another aspect of the invention, a tension controllingapparatus is provided which includes driven rollers means drivinglyengaging a lead of the web and a floating roller yieldably biasedagainst the web lead to maintain the tension in the lead substantiallyconstant. The floating roller has a limiting position to which it ismovable under varying web conditions and means are provided which areresponsive to movement of the roller to its limiting position to actupon the driven roller means so as to move this means and the web in thedirection to free the floating roller and allow it to move away from itslimiting position to resume control of the web tension.

The above mentioned and other objects, aspects and advantages of theinvention will be further apparent from the following detaileddescription of preferred embodiments thereof and from the accompanyingdrawings in which:

FIG. 1 is a schematic view of a multi-unit web printing machine adaptedfor register control according to the pesent invention;

FIG. 2 is a view of a portion of the same machine;

FIG. 3 is a sectional View thereof taken on line 33 of FIG. 2;

FIG. 4 shows schematically a modified form of register control apparatususeful in the machine;

FIG. 5 shows schematically another modified form of such apparatus;

FIG. 5 is a diagrammatic view of an embodiment of the invention whereinthe web passing between two rotary printing units is inverted by theaction of turn bars;

FIG. 6 is a diagrammatic view of an embodiment of bodiment; and

FIG. 8 shows a modification of the embodiment of FIG. 7.

In the multi-color web printing press of FIG. 1, a web W is unwound froma rollstand RS, which preferably is an automatic splicing rollstand ofthe type disclosed in my copending US. Patent No. 3,103,320.

From the rollstand RS the web W travels over suitable guide rollers to aprinting unit P-1 which applies patterns and register marks to the web,typically in yellow.

The web is then moved successively through printing units P-2, P-3, P-4which typically print the web in red, blue and black, respectively.After leaving unit P-4, the web travels to a processing unit P-S whichmay take any of various forms. For example, it may be a perforatingunit, a slitting unit, a cross-cutting unit, an embossing unit or a setof collating rollers associated with a folding unit.

If the Web W is preprinted, it may be threaded along an alternate pathindicated in dash lines in FIG. 1, directly from the rollstand RS to theunit P-2.

If the web is to be printed on both sides, it may be printed on one sideby the unit P-1 and thereafter guided along a path shown by the chainlines in FIG. 1 to a turn bar unit TB which turns the web over, so thatit may be thereafter printed on its opposite side by the units P-2, P-3,and P4. A similar turn bar arrangement may of course be provided betweenany two of the printing units.

The printing units, as seen in FIG. 2 in respect to units P-1 and P-2,may each comprise an ink fountain system 10, shown only in diagram,contacting and applying printing ink to an engraved gravure cylinder 12against which a rubber covered or equivalent nip roller 14 presses theweb tightly under force provided by a steel back-up or impressioncylinder 16.

The gravure cylinder 12 of each printing unit is driven from the mainpress drive shaft 20 which is driven from the main press motor M bybelts 22 trained around a pulley 24 on the output shaft of the motor anda pulley 26 on the drive shaft. Each nip roller 14 is fri-ctionallydriven by the coacting gravure cylinder. Motor M is controlled from acontrol panel 28 having a push button station 30. The station 30includes a button 30a for servicing the press, threading the web etc., abutton 30b for normal drive or operation of the press, a button 300 foremergency press stops, and a button 30d for normal press stops. Currentis delivered to push button station 30 from main supply lines L1, L2,through an on-off switch 32.

After leaving a printing unit, such for example as the unit P-l in FIG.2, the Web is guided through a drying oven 0 by a plurality of guiderollers 34. From the oven, the web is guided to free running coolingcylinders 36 around which the web is trained in serpentine fashion. Fromthe cylinders 36 the web travels over guide rollers 38, 40 and 42, overa floating roller 44, thence in serpentine fashion around drive rollers46 and 48, and then over guide roller 50 to the printing unit P-Z. Asimilarly constituted path of travel may be provided between units P-2and P-3 and between units P-3 and P-4.

The drive rollers 46 and 48 form a part of a longitudinal registercontrol device, indicated by the block R-2 in FIG. 1. As seen in FIG. 1,one such longitudinal register control device R-2, R-3, R4 or R-S isprovided between each two successive printing units and between the lastprinting unit P-4 and the web processing station P-S. If the web is tobe collated at P-S with other webs such, e.g., as the webs W-2, W-3 andW-4 shown in phantom lines in FIG. 1, then similar register controldevices R-6, R-7, and R-8 are provided for these other webs and aredriven in synchronism with the device R-S.

The device R-2 as seen in FIG. 2 includes a displaceable carriage 52rotatably supporting the drive rollers 46 and 48. A V-belt pulley 54 issecure-d to an extension of the drive roller 48 and is driven by aV-belt 56 trained around a V-belt pulley 58 mounted on a fixed axis. Thepulley 58 is driven by a drive shaft 18 driven from the main press driveshaft 20. The roller 48 is driven from the roller 46 by suitable gearmeans (not shown), so that when the motor M is active the rollers 46 and48 are driven in opposite directions and in synchronism with the unitsP-1 and P-2 and cooperate with these units to propel the web along theextended path between these units.

The carriage 52 has a mounting arm securing it for pivotal reciprocatingmovement on a shaft 62 pivotally mounted in the press frame. An arm 64is secured at one end to the shaft 62 and at its other end carries apivotally mounted nut 66 which is engaged by a screw 68 coupled to theoutput shaft of a reversible electric motor 70 so that upon actuation ofmotor 70 the carriage 52 is pivoted about the axis of shaft 62 to movethe drive rollers 46 and 48 toward or away from the printing unit P-2.

Pivotally mounted on the carriage 52 are arms 72 carrying pressurerollers 74 at their outer ends. Spring means (not shown) continuouslyhold the rollers 74 and thereby web W in non-slip driving contact withthe drive rollers 46 and 48, so that movement of the rollers 46 and 48toward or away from the unit P-2 moves the web portion engaged by theserollers toward or away from this unit.

It will be evident that such displacement of the driven rollers 46, 48has the effect of transiently varying the speed of movement of theportion of the web engaged by these rollers, relative to the speed ofthe portion of the Web engaged by the unit P-2, and thus will vary thestretch of the web lead extending from the rollers to the unit P-2.

The belt contacting radius of the V-belt pulley 58 is variable inresponse to variations of the tension of V- belt 56. The pulley 58 maybe, for example, of the type disclosed in my United States Patent No.2,812,666. Tensioning rollers 76 carried on the free ends of arms 78clamped to stub shafts 80 bear against the V-belt and are adjustable byadjustment of the arms 78 on the shafts 80 to vary the belt contactingradius of the pulley 58 so as to establish the desired initial ratio ofthe peripheral speed of the rollers 46 and 48 to the peripheral speed ofthe unit P-2.

It will be seen that the aforedescribed displacement of the rollers 46and 48 toward or away from the unit P-2 in response to actuation of themotor 70 will vary the tension of the belt 56 and thereby vary the beltcontacting radius of the pulley 58 and the speed of the belt 56, wherebyto vary the rotational speed of the rollers 46 and 48 relative to thatof the. printing unit. Specifically, movement of the rollers 46 and 48toward unit P-2 increases the rotational speed of the rollers 46 and 48,and movement of the rollers 46 and 48 away from unit P-2 decreases theirrotational speed. Thus, as these rollers are moved closer to theprinting unit their peripheral speed and the speed of the web .portionpropelled by them is increased relative to the speed of the web portionengaged by unit P-2, while the opposite effect is obtained when theserollers are moved farther away from the printing unit. That is, theeffects of the bodily movement and the simultaneous speed variation ofthe rollers 46 and 48 are additive, so that there is a dual effect uponthe stretch of the web lead extending from these rollers to the unitP-2.

Photoelectric scanning heads 82 and 84 are disposed at opposite sides ofthe variably stretched web lead between the carriage 52 and theproximate printing unit. These scanning heads may be of the typecommercially available from the Specialty Control Department of theGeneral Electric Co., Waynesboro, Virginia, as Item No. CR 7515P20 2G4.A scanning head of the identified type includes a light source directinga beam of light against the web and a photoelectric cell which measuresthe intensity of the light of the beam that is reflected by the webtoward the cell.

- One of the scanning heads emits an electrical signal each time aregister element, such, for example, as a register mark applied to theWeb W by the printing unit P-l, passes a fixed point in the area scannedby the head. mark applied to the web W by the printing unit P-1, P-2,the head 82 emits the register signals. When the web leaving unit P-1 ispassed through a turn bar unit TB so that the marks printed on the webP-l are on the upper side of the web approaching unit P-2, the head 84emits the register signals.

The signals from head 82 or 84 are compared with a series of electricalsignals emanating from a photoelectric selector switch 86 which isdriven from the gravure cylinder 12 of unit P-2 through a pulley 88,non-slip belt 89 and pulley 91. The switch 86 may be of the typecommercially available from the Specialty Control Department of theGeneral Electric Co., Waynesboro, Virginia, as Item No. CR 7515PI45G4.

The signals from head 82 or 84 and those from switch 86 are fed to andcompared by a control panel 90, which may be of the type commerciallyavailable from the Specialty Control Department of the General ElectricCo., Waynesboro, Virginia, as Item Nos. 357515-CT A1. The control panel90 is operative to generate an error signal in response to the detectionof a lack of synchronization between the signals from the head 82 or 84and those from the switch 86, and these error signals, which areproportional in magnitude to the register error detected, are fed to thereversible motor 70 to rotate that motor in the direction and to theextent required to correct the detected error.

Specifically, if the signals from head 82 or 84 lag behind those fromswitch 86, indicating that the register marks on the web W are laggingbehind the required register position with respect to the gravurecylinder 12, motor 70 is rotated in the direction to pivot carriage 52clockwise (as viewed in FIG. 2) about the axis of shaft 62, so that therollers 46 and 48 are moved toward unit P-2 to displace the web portionengaged by them toward that unit andsimultaneously increase therotational speed of the rollers and thus, by both of these actions,increase the relative linear speed of the web portion propelled by therollers. As a result, the stretch of the relatively short Web leadbetween the rollers 46 and 48 and the cylinder 12 will be reduced tomove the register marks on the web directly to their position of correctregister with the cylinder.

If the signals from head 82 or 84 are ahead of those from switch 86,indicating that the register marks on web W are ahead of the requiredregister position with respect to the gravure cylinder 12, motor 70 isrotated in the direction to pivot the carriage 52 counterclockwise, thusdisplacing the rollers 46 and 48 and the web portion engaging themfarther away from the cylinder and simultaneously and proportionallydecreasing the rotational speed of the rollers so as to increase thestretch in the web lead between the rollers and the cylinder.

Since the register control device R-Z operates on and varies the stretchin only a relatively short lead of the web approaching the printingunit, the ratio of the resulting corrective movement of the individualmarks on the web to the applied correcting displacement of the registerdevice is considerably greater than in known register control systems,with the important results that the detected errors are corrected morequickly and more accurately than by the known systems, and with asmaller amount of corrective displacement and little or no hunting ofthe register device.

Further the corrective action obtained by variations of the relativespeed of the rollers 46 and 48 has the important advantage of beingeffected at any speed of operation of the printing machine, so that theweb may be held in register at high or low press speeds as well as whenthe press is undergoing acceleration or deceleration.

Any displacement or rotational speed variation of the rollers 46 and 48of course tends also to vary the tension and thereby the stretch of therelatively long web lead extending from the preceding printing unit P-lto these rollers. Such a variation is prevented, however, by thefloating tension control roller 44 of the device indicated at T-2 inFIG. 1, over which roller the web lead from unit P-1 passes as itapproaches the driven rollers 46 and 48.

As seen in FIG. 2, the device at T-2 includes an arm 92 which may be oneof a pair of arms pivotally mounted between their ends on a shaft 94 androtatably carrying the floating roller 44 at one of their ends. Theother end of arm 92 is secured to the piston of a fluid pressurecylinder 96 pivotally suspended from the frame of the press. A conduit98 extends to cylinder 96 from a source of fluid under pressure (notshown), and a pressure regulator 100 is provided in the conduit 98 toadjust the fluid pressure acting against the piston of the cylinder. Themagnitude of the fluid pressure is indicated by a pressure gauge 102which may be calibrated in units of web tension to provide a continuousand easily readable indication of web tension.

The web W wraps around the roller 44 in a direction such that the pullof the tensioned web on this roller urges the roller downwardly with aforce that is resisted by the pressure of the air acting on the pistonof the cylinder 96, so that the magnitude of the tension in the web leadbetween the drive rollers 46 and 48 and unit P-1 is determined by themagnitude of the air pressure and is maintained at that valueirrespective of web and roller displacements cause-d by bodily movementsand variations in the rotational speed of the driven rollers 46 and 48.

The tension control device T-2 and the register control device R-2 thusact in conjunction to vary the tension and thereby the stretch of therelatively short lead of the web between the rollers 46 and 48 and theunit P-2 in the sense'and to the extent required for quick correction ofdetected errors in register of the successive printed patterns or otherprocessed locations on the web with respect to the gravure cylinder 12,while maintaining the tension and thereby the stretch of the relativelylong lead of the web between unit P-1 and device R-2 substantiallyconstant so as not to disturb the register of the web to the unit P-1.

The non-slip engagement of the web by the rollers 46 and 48, in additionto confining the register corrective action to a relatively short weblead, also will serve to hold the web in its transient position relativeto the gravure cylinder 'when the machine is stopped for any reason.This has the important result that when the machine is stopped forservicing and, as is customary, the nip roller 14 and impressioncylinder 16 are raised out of contact with the web and gravure cylinder12 to enable slOW rotation of the cylinder 12 through the ink fountain10, the rollers 46 and 48 continue to hold the web in register with thefollowing printing unit so that the web is still in register when thecylinders are reengaged for restarting of the press.

Since the driven rollers 46 and 48 of the register control devices R-2,R-3 and R4 are driven from the same rotary power source as the printingunits, i.e., from the main press drive shaft 20, it is necessary, inorder that the gravure cylinders may be rotated slowly as abovedescribed, that the drive rollers be disconnected from the shaft 20during stoppage periods. As shown most fully in FIG. 3, this may beaccomplished by means of a clutch 104 provided in the driving connectionbetween each shaft 18 and the variable diameter pulley 58 driving theassociated rollers 46 and 48.

Each clutch 104, as seen in FIG. 3, comprises a first serrated disk 106keyed to a shaft 108 driven from shaft 18 and a second serrated disk 110fixed to the pulley 58 and freely rotatable on and axially slidablealong an extension 112 of the shaft 108. The disks 106 and 110 are heldin engaged position against the bias of a spring 114 by a solenoid 116having its plunger connected to one end of a lever 118 which carries atits other end a pin 120 riding in a groove 122 in disk 110. Thesolenoids 116 associated with the respective clutches 104 of the severalregister control units are connected into an electrical circuit 124which is broken by depression of the threading or service button 30a,whereby to deenergize the solenoids and allow the disks of each clutchto be moved to a disengaged position by the action of spring 114.

The maintenance of established register conditions from one operatingperiod to another, notwithstanding stoppage of the machine and slowrotation of the printing cylinders during the period of stoppage, isfurther promoted by the provision of means which act to halt therotation of each gravure cylinder at a predetermined angular positionthereof whenever a signal to stop the press is given. Thus, after beingrotated slowly during a period of press stoppage, the gravure cylindersare halted at the same angular positions they occupied when the presswas initially stopped, so that when they are reengaged with the web theywill continue to be in register with it.

Suitable means for this purpose include a cam 126 carried on a rotaryelement of the machine that is positioned according to the position ofthe printing cylinders, for example, as here illustrated, on the disk106 of the clutch 104 provided for unit R-2. The cam 126 is adapted toengage a switch 128 during each revolution of the disk. The switch 128is in an auxiliary electrical circuit 130 to the press driving motor M.The auxiliary circuit 130 also passes through a switch 132 controlled bythe coil 134 of a relay 136, and through a switch 138 controlled by theupper coil 140 of a latch relay 142.

During operation of the press, the switch 132 of relay 136 is held in anopen position by a circuit 144 passing through and energizing the coil134 of this relay, so that depression of the switch 128 by the cam 126as the press rotates has no electrical effect until a signal to stop thepress is given by depression of button 30a.

Upon the depression of button 30d, the drive button 30b is released tobreak circuit 146 to the motor M, but simultaneously circuit 144 isbroken so that the switch 132 is closed and the auxiliary circuit 130 iscompleted to the motor, which thereby continues to be energized. Closingof the switch 132 also completes a circuit 148 to the lower coil 150 ofthe latch relay 142, to energize that coil and pull the latch plate 152controlled thereby clear of the switch 138. However, since closing ofthe switch 132 also completes a circuit 154 through the upper coil 140,the switch 138 remains closed until with continued rotation of the disk106 the switch 128 is opened by the cam 126, thus breaking the circuit130 to the motor and stopping the press. Means (not shown) are alsoprovided to release the button 30d upon actuation of the switch 128 andthereby open the switch 132 so that the subsequent closing of the switch128 as the cam 126 continues past it will not re-energize the motor.

After the press has stopped, the service button 30:: may be depressed tobreak the circuit 124 and disengage the clutch disks 106 and 110. Thegravure and pressure cylinders of each unit then may be separated (bymeans not shown), and the press restarted by depression of the button30b to rotate the gravure cylinders slowly. After the servicing orthreading operation has been completed, the press is again stopped bydepression of the button 30a, the gravure cylinders being then stoppedby the cam and relay mechanism above described in the angular positionthey assumed when the press was initially stopped, so that whenreengaged with the web they will continue to be in register with it.

It will of course be apparent that prior to restarting the press torotate the gravure cylinders during the servicing period it will benecessary to disengage all other web driving devices, such, for example,as the drives for the rollstand RS and any web driving elements of theturn bar system TB, from the main press drive shaft 20. This may beaccomplished by electromagnetic clutches (not shown) which may bearranged to be deenergized and disengaged simultaneously withdisengagement of the clutches 104 upon depression of the button 30a.

Separation of the cylinders at each printing unit causes the web to hangslack between successive register control devices or, in the case of theunit P-l, to hang slack between the register control device R-2 and therollstand RS. It will be apparent that the movable rollers 44 of thetension control devices, if permitted to act under their normal bias,would run out this slack under the force of the fluid pressure in thecylinders 96 and tend to destroy the established register between theweb and the processing units. To prevent this, means are provided tolock the roller 44 of each of the devices T-2, T-3 and T4 in the workingposition which it occupies prior to separation of the cylinders grippingthe web at the processing stations. These means, as seen in FIG. 2,include for each unit such as T-2 an arm 156 formed at one of its endswith a notched arcuate surface 158 and mounted on the stub shaft 94carrying the movable roller 44. A toothed finger 160 engageable with thenotched surface 158 is formed on one end of a bellcrank 162 pivotallymounted on a stub shaft 164. The other end of the bellcrank is securedto one end of a spring 166 continually urging the bellcrank to moveclockwise about the axis of shaft 164 to urge the finger 160 intoengagement with a notch or serrations of the surface 158. This other endof the bellcrank is also connected to the plunger of a solenoid 168which when energizezd holds the finger 160 out of engagement with thesurface 158 against the bias of the spring 166.

The solenoids 168 respectively associated with the tension controldevices T-2, T-3 and T-4 are connected into the electrical circuit 124so that upon depression of the servicing button 30a, following stoppageof the press by depression of button 301), the rollers 44 are locked intheir respective transient positions and are thus prevented from runningout the slack introduced into the web upon the subsequent separation ofthe printing cylinders at the various units.

As previously indicated, the web in passing from one printing unit tothe next is passed over a pluraliy of guiding rollers or cylinders. Someof these, such, e.g., as the cooling cylinders 36 of FIG. 2, have arelatively large mass and for that reason the usual practice has been todrive web guiding rollers from the main press drive so that they willrotate in unison with the printing units and cooperate with the latterto propel the web at uniform speed. However, because of expansion andconcontraction of these rollers or cylinders due to variations of theirtemperature, their diameters tend to vary with the result that the speedat which they propel the web is also varied. Such speed differentialstend to produce excessive looseness or tightness of the web, therebytending to produce register errors, side weaving or even breakage of theweb.

According to a further feature of the present invention, the web guidingrollers or cylinders over which the web is trained to pass betweensuccessive processing units are arranged as free running or idlerrollers, so that they may be driven peripherally by the friction of theweb when the web is tensioned against them. Such an arrangement isentirely practical for normal starting and stopping of the press, atwhich time acceleration or deceleration is controlled and gradual. Whileit would ordinarily be impracticable, because of the need for emergencystops which require that the press stop quite abruptly, e.g., within afew revolutions of the processing cylinders, and would result indisplacement or breaking of the web by the drag of the free runningrollers, this problem is avoided according to the invention by theprovision of means acting automatically to release the tension in theWeb leads engaging these rollers whenever an emergency stop occurs, sothat the rollers may coast to a stop without displacing or damaging theweb.

These tension releasing means include, for each tension control device,a solenoid 170 having its plunger connected to the spool of a controlvalve 172 interposed in the conduit 98. The spool is continuously urgedby a spring (not shown) toward a position in which communication betweenthe cylinder 96 and the source of fluid pressure is blocked and thecylinder is vented through an exhaust conduit 174 to the atmosphere. Thesolenoid 170 when energized holds the valve spool against the resistanceof its spring in a position in which the fluid presure cylinder ismaintained in communication with the fluid source so as to tension theroller 44 against the web with a force dependent upon the setting of thepressure regulator 100.

The solenoids 170 associated with the tension control rollers 44 areconnected into a circuit 176 which is broken by depression of theemergency stop button 30c, so that upon an abrupt stoppage of the pressthe fluid pressure.

1 1 on the rollers 44 is released to free the Web from tension againstthe guide rollers, including the cooling cylinders 36, and allow thesenormally Web-driven rollers to coast to a stop.

The circuit including the solenoids 170 also includes, in series withthe solenoids, a plurality of web break detectors WB of knownconstruction, which are held in a circuit closing position by the normaltension of the web but which move to a position to break the circuit 176upon a substantial decrease in the sensed web tension occurring, forexample, upon a break in the web. Accordingly, the pressure biasing therollers 44 against the web is released upon an abrupt press stoppageoccurring either as a result of depression of the emergency stop button300 or as a result of a breaking or loss of tension of the web. It willbe understood that the abrupt stop; page of the press ocurring uponbreakage of circuit 176 is brought about by dynamic braking means (notshown) of known construction and operation.

If desired, the exhaust conduit 174 of any or all of the control valves17;; may be provided with a pressure regulating device 178 that isadjustable to establish at any of various desired values the pressure ofthe fluid remaining in the cylinders after deenergization of thesolenoids.

Whenever the press is stopped with substantial inequalities of webtension existing along the various leads of the web, there is a tendencyfor the web, in an attempt to equalize its tension, to rotate the webregister units contacting it. A like tendency may result from accidentalcontact of the web with the rotating gravure cylinders or from changesin the press room temperature or humidity conditions. The registercontrol units when not running may also tend to be rotated as a resultof accidental jarring of parts of the press during work on them byoperating personnel. Such rotation is made possible by the fact thatthese units are declutched from the main pres-s drive when the press isstopped. If allowed to take place, it would result in a shifting ofsections of the web out of their registered relationship to theprocessing units. To prevent this, further means are provided accordingto the invention which act automatically upon stoppage of the press toclamp the web firmly at spaced locations therealong so that it will notexert a rotating force on the rollers of the register control units.

' Such clamping means are shown at the unit P-1 in FIG. 2 and areindicated generally as 180. Each of them includes a bellcrank 182pivoted on a stub shaft 184. One end of the bellcrank 182 is formed withan arcuate clamping element 186 having a radius of curvaturesubstantially equal to that of a web guiding roller 34 with which it isadapted to co-act. The other end of the bellcrank is secured to a spring187 continually urging the bellcrank in a direction to move the clampingelement 186 into engagement with the web passing over the roller 34.This end of the bellcrank is also connected to the piston of a fluidpressure cylinder 188 to which fluid under pressure is supplied througha conduit 190 at a pressure determined by the setting of a pressureregulator 192 interposed in conduit 190, and indicated by a pressuregauge 194 also interposed in conduit 190. A control valve 196 in theconduit 190 controls the delivery of fluid pressure to the cylinder. Asolenoid 198 has its plunger connected to the spool of the valve 196 andnormally holds the valve open against the resistance of an internalvalve spring (not shown) to maintain fluid pressure in cylinder 158 andthereby hold clamping element 186 away from roller 34.

The solenoid 198 associated with the various clamping devices areconnected into a circuit 200 which is broken by depression of eitherservice button 30a or emergency stop button 30c, so that upon adepression of button 30a following a normal press stop, or upon anemergency stop of the press by depression of button 300,

the various web clamping devices 180 act to firmly grip the web andprevent longitudinal shifting of the same during the stoppage period.

Since all the rotating members of a printing press require at least afraction of a revolution, and often appreciably more, in order to cometo a stop, it is necessary to delay the action of the clamp devices 180for a time, following a signal causing the press to stop, sufficient toinsure that the web will be at rest when it is clamped. This delay isprovided by incorporating a time delay relay 202 in the circuit to eachclamping solenoid. Each relay 202 may be, e.g., one of the thermal type,which continues to conduct current for a fixed time after the electricalcircuit including it is broken by a signal for a press stop, or bydepression of service button 30a, after which time the electricalcircuit to the solenoid is broken and the clamping device moved to itsweb clamping position.

It may be desired at various times to feed an unprinted or white webfrom the rollstand directly to the printing unit P-2, in which event theregister control device R-2 cannot function for lack of register markson the web. When this occurs it may happen that the carriage 52 of thedevice R-2 is so positioned that the rotational speed imparted to therollers 46 and 48 by the belt contacting radius of the variable diameterpulley 58 is slightly too high or too low as compared to the speed ofthe printing units. Such a speed discrepancy will tend progressively tolengthen or shorten the web lead between the rollers 46 and 48 and theunit P-1 and correspondingly to displace the floating roller 44. Thatroller 44, however, will soon reach a limit of its range of movement,and if the speed discrepancy were allowed to continue the web tensionwould thereafter increase so as to break the web, or decrease so as tomake the web lead uncontrollably slack.

In order to prevent any such difliculty, further means are providedaccording to the invention for automatically displacing the carriage 52in the direction and to the extent required for eliminating the speeddiscrepancy, whenever the floating roller 44 reaches either limit of itsnormal range of movement. These means, as seen in FIG. 2, include an arm204 formed as a lower extension of arm 156 of the tension control deviceT-2 and so arranged that as the roller 44 approaches either limit of itsmovement this arm 204 will actuate one switch of a pair of limitswitches 206 and 205 disposed on either side of the arm. The switches206 and 205 are electrically connected to the control panel by circuits207 and 208, respectively. The circuitry is such that when either switchis actuated the pilot motor '70 is energized through the control panel90 in a sense to move the carriage 52 in the direction to prevent theimpending harmful increase or decrease in the web tension. A cut-offswitch 209 is provided in the circuits 207 and 208 to incapacitateswitches 206 and 205 when printed paper is being supplied to the unitP-2.

It is desirable under certain conditions that the energization of thepilot motor 70 and displacement of the carriage 52 in response toactuation of either of the switches 206 and 205 be made cyclical orintermittent. This is accomplished by the phasing device shown generallyat 210 in FIG. 2. The device 210 includes a gear reduction unit 212supported in a position adjacent to printing unit P-2 and driven fromthe latter by a belt 214 engaging a pulley 216 secured to the inputshaft of the reduction unit. Secured to the output shaft of the unit 212is a cam 218 which cyclically actuates a switch 220 in the electricalcircuits 207 and 208 so that the motor 70 is energized only when one ofthe limit switches is actuated by the arm 204 and the switch 220 isactuated by the cam 218. A cut-off switch 222 is provided toelectrically by-pass the switch 220 when continuous rather thanintermittent energization of pilot motor 70 is desired.

FIGS. 4 and 5 show modified forms of register control devices which maybe used ahead of the several printing or other web processing units inplace of the device shown at R-2 in FIG. 2.

The register control device of FIG. 4 is similar to that of FIG. 2,excepting that its web driving rollers 46a and 48a are mounted on acarriage 52a which is reciprocable by a pilot motor 70a along fixedguide rods 224. V-belt tensioning rollers 76:! are supported against theflights of the belt, so that a displacement of the carriage on the rodsvaries the length of the webpath and the stretch of the web lead fromthe register control device to the associated processing unit andsimultaneously displaces the V-belt 56a relative to its tensioningrollers 76a, thereby varying the V-belt tension, the belt contactingradius of the pulley 58a and the rotational speed of the rollers 46a and48a.

In the register control device of FIG. 5, the web driving rollers 46band 48b are mounted on fixed axes in the press frame, and the web Wtraveling from these rollers to the processing unit is passed about adisplaceable roller 226 carried on one arm of a bellcrank 228, the otherarm of which carries a belt tensioning roller 76b continuously bearingagainst the V-belt 5617. A pilot motor 70b is connected with thebellcrank so that upon rotation of the motor 70b for the correction of aregister error, the web positioning roller 226 is displaced to vary thelength of the web path and the stretch of the web lead to the associatedprocessing unit, and the belt tensioning roller 76b is displacedcorrespondingly to produce proportional variations of the tension of theV-belt 56b, the belt contacting radius of the pulley 58b and therotational speed of the web driving rollers 46b and 48b.

It will be understood that the references herein to maintaining asubstantially constant web tension, such as in the lead of the webextending from one processing unit to the web-driving register controldevice associated with the next processing unit, do not imply that thetension will have the same magnitude in successive or differentlydirected sections of the same web lead. Although the magnitude of thetension is kept substantially constant in each section, it increasesstepwise as the web passes successively in contact with rollers, bars orother elements guiding it along its path of travel, until the webreaches a Web propelling unit, such as the driven rollers of eachregister control device, that propels it with an energy input overcomingaccumulated drag effects of the press elements previously contacting it.

When a machine according to the invention makes use of a conventionalturn bar system for inverting the web as it is passed between twoprinting units, for example, as diagrammed .at TB in FIG. 1, aconsiderable drag is exerted on the web being drawn over the turn bars.The magnitude of the tension in the web section leaving the turn barsis, therefore, considerably greater than that prevailing in the websection entering them.

The tension value in each of those sections, as in each other section ofthe web lead extending from printing unit P-l, may be kept substantiallyconstant by the action of a biased roller device, e.g., device T-2, foras long as the tension building effects of the two bars and of the otherelements contacting the web lead are substantially constant and do notaccumulate tension in the web to an excessive level before the webreaches the driving rollers of the register control device, e.g., deviceR-2.

In some circumstances, however, as where the web lead is likely to besubjected to irregular tension building effects before reaching the turnbar system, it is important to make sure that the tensions in the websections entering and leaving the turn bars will be kept at selected,substantially constant values well suited to steady travel of the webover the bars and from them to the device registering the web to thenext printing unit. Otherwise, difficulties tending to break the web,throw it sidewise along the bars, limit its speed and/or bring it out ofregister at the preceding printing unit are likely to be encountered atthe turn bars.

Such difliculties can be materially reduced or avoided and the requiredsteady travel of the web over the turn bars assured according to theembodiment of the invention illustrated in FIG. 6. This embodimentprovides for the maintenance of a definite, pre-selected tension valuein the web section entering or about to enter the turn bars and for theapplication of propelling energy to the web section leaving or closelybeyond the bars, so as to overcome the accumulated drag on the latterand bring the tension level to a materially reduced magnitude as theinverted web beyond the bars is registered to the next printing unit.

The arrangement of FIG. 6 may be considered essentially the same as thathereinabove described for control of the web traveling between printingunits P-1 and P-2 of FIGS. 1 and 2, exceptiong that the tension controland register control devices between the printing units, such as thedevices T-2 and R-2 of FIG. 2, operate respectively on web portions justahead of and closely beyond the turn bars, instead of being located awayfrom the turn bars and closer to the second printing unit.

As seen in FIG. 6, a set of turn bars TBl and TB2 for inverting the webW, together with their bay window (i.e., a roller or rollers, not shown,engaging the web loop running between the two bars), is disposed betweena register control device D and a floating roller device E thatmaintains substantially constant tension in the web lead extending fromthe first printing unit A to the register control device. The device Doperates on the web lead extending to the second printing unit B, so asto held the web in register with that unit by variation of its stretchas above described.

The device D may be of any of the types shown in FIG. 6 or at R-2 inFIG. 2 or in FIG. 4 and FIG. 5. Its

web positioning rollers or roller are positioned by a pilotmotor PM inresponse to signals from a photoelectric register mark scanner C,essentially as described with reference to unit R-2 of FIG. 2. Thetension control device E is similar to that shown at T-2 in FIG. 2.

The constantly biased floating roller at E establishes and holds a quitedefinite, selectable value of tension in the web section entering theturn bars. By keeping this value substantially constant, it also keepsthe respective tension values in the web sections between and leavingthe bars TBI and TB2 substantially constant, up to the point of drivingengagement of the web W by the driven rollers of the register controldevice D. These rollers in turn continuously supply the energy requiredto propel the web away from the bars and to bring the tension level inthe web lead leaving the rollers to a reduced average value enabling thedevice D to perform its register control functions without danger ofoverstressing that web lead. 1

In circumstances where the accumulated tension level in the web enteringthe turn bars may be too high, as Well as possible too irregular, forassurance of satisfactory operations at high web speeds, such, forexample, as in the processing of delicate web material or in some casesof the use of an oven or other web heating means followed by coolingrollers for drying a printed paper web before it is inverted and passedto the next printing unit, it is advantageous not only to achieve theeffects of the arrangement of FIG. 6 but also to have the definitetension level that is set and held in the web section entering the turnbars reduced substantially below the tension level normally built up inthe web as it travels to the turn bar system.

To achieve this end, instead of providing as at E in FIG. 6 mere-1y asimple floating roller constantly biased against a loop of the web aboutto enter the turn bars, the tension control device there provided may beof a web propelling, floating roller type, such, for example, asillustrated at E1 in FIG. 7; and a simple floating roller hearing underconstant bias against a loop of the web leaving the bars, as illustratedat E2 in FIG. 7, is disposed between the bars and the register controldevice D1 propelling the web away from the bars.

The tension control device E1 in FIG. 7 has web propelling rollers 700and 701 mounted on a reciprocable carriage 702 and driven by a variablespeed V-belt drive, in essentially the same manner as the registercontrol device in FIG. 4. Instead of being positioned by a pilot motor,however, these rollers are held in a floating condition by a balance ofseveral forces. The tension of the web section W1 being drawn to themand the reaction of their driving V-belt 704 to the pressure of thatbelt against the rollers 705, 706 tensioning it continuously urge thecarriage in one direction, while the tension of the web section W2leaving the device to enter the turn bars and the pre-selected bias ofthe air cylinder 708 acting upon the carriage urge the carriagecontinuously in the opposite direction, i e., toward the turn bars.

Since the constantly biased floating roller 710 of device E2 keeps thetension level in the web section W5 leaving the turn bars at a constantvalue set by the air pressure in its air cylinder 712, substantiallyconstant, though different, tension levels are also maintained in therespective web sections entering and passing between the turn bars.Therefore, the aggregate force urging the carriage toward the turn barsis substantially constant.

The aggregate force urging the carriage away from the turn bars is alsoconstant when the tension in the web section W1 being drawn to therollers 700, 701 is constant at a value in balance with the other forcesacting on the carriage. The carriage then stands still and the webdriving speed of its rollers is constant. But when a variation oftension begins to develop in the web lead approaching its rollers, thecarriage moves incrementally to restore the balance of forces, and thetension of V- belt 704 is thus varied correspondingly so as to vary thespeed of the rollers and thereby restore the tension in that web lead toa pre-set value determined by the pressure applied to the cylinder 708biasing the carriage.

Accordingly, the tension in the web running to the turn bar system fromthe first printing unit is kept substantially constant by the action oftension control device E1, which device applies propelling energy to theweb so that the web section W2 entering the turn bars can have a tensionlevel reduced as desired for steady and reliable movement of the webover the turn bars; while the simple floating roller 710 of device E2 atthe exit side of the bars sets and keeps the respective tension levelsof the web sections entering, between and leaving the bars substantiallyconstant at the desired values determined by the pressure applied to itsair cylinder 712. Moreover, it does this notwithstanding the webregistering actions of the device D1 which continuously propels andpositions a portion of the web beyond device E2 so as to reduce thetension level produced in the web by the drag of the turn bars and toregister the web lead drawn from device D1 to the next printing unit, inthe manner hereinbefore described.

A further modification of the system according to FIG. 7 may beadvantageous in cases where the cumulative drag of the two turn bars onthe web would raise the tension level in the web section leaving thembeyond a limiting value desired for the material being processed. Forthe avoidance of difliculties in such cases, a roller -or set of rollersguiding the web loop at the bay window of the turn bars may be made toserve as the variable speed floating roller means of a web propellingtension control device, as illustrated schematically at E3 in FIG. 8.

The device E3 is quite similar to the device E1 already described. Partsof it corresponding substantially to parts seen in FIG. 7 are indicatedby corresponding primed reference numerals,

It will be understood that the rollers 700', 701' of wet propellingtension control device E3 at the bay window of the turn bar system willkeep the web sect-ion WE running from the first turn bar TBl under asu-bstantialh constant tension determined by the setting of the fluicpressure in cylinder 708 biasing carriage 702' and tha they will propelthe return web section W4 toward the second turn bar TB2 under a reducedlevel of tensior determined by the fluid pressure in the cylinder 712biasing the floating roller 710 of device E2 (FIG. 7).

It will also be understood that where the turn bar sys tem is providedwith a web propelling tension control device such as device E3 actingupon the web loop at the bay window, it may be feasible under someoperating conditions to provide ahead of the first bar, instead of asimilar device such as device E1, a simpler floating roller device as atE in FIG. 6; or even to dispense with all tension control means ahead ofthe first bar. For most conditions, however, the latter is notadvantageous, and an arrangement such as that of FIG. 6 or FIG. 7 is tobe preferred over one providing web propulsion and tension control atthe bay window.

From the foregoing it will be seen that the present invention provides asystem of apparatus for a multi-unit web processing machine which,whether the web is passed directly from unit to unit of the machinewithout inversion or is inverted between successive units so that it maybe processed on first one and then the other side, acts quickly andpositively to correct detected errors in the register of the web to eachprocessing unit; performs its corrective function as to each unitwithout excessive hunting and without disturbing the register of the webto the other processing units of the machine; holds the web inregistered relation to the various processing units during stoppage ofthe machine; and acts upon abrupt stoppage of the machine to free thevarious idler rollers peripherally driven by the web from constraint bythe web and thereby prevent these rollers from damaging the web.

It will be seen, more particularly, that the present invention providesa system of apparatus for a multi-color rotary gravure press which acts,during operation of the press, to maintain correct register of the webto the various printing units and acts, upon stoppage of the press andfreeing of the web at the printing units by separation of the coactingcylinder sets, to hold the web in place relative to the separatedcylinders; and which acts to halt the cylinders following their slowrotation during the stoppage period at approximately the angularposition they assumed when the press was initially stopped so that whenreengaged with the web they will continue to be in register with it.

While illustrative embodiments of the invention have been shown anddescribed, it will be understood that the new features of the inventioncan be utilized in many other ways and are not restricted to theillustrative embodiments except as may be required by a fairconstruction of the appended claims.

What is claimed is:

1. In a multi-unit web processing machine including first and secondrotary processing units for engaging and propelling a web and betweenwhich the web travels under tension through an extended path, and meansfor driving said units in synchronism, each of said units normallyholding the web in non-slipping relation thereto, said first unit havingan element thereon that registers cyclically with successive points onthe web which are to be maintained continually in register with anelement on said second unit;

register control means, including driven roller means non-slippablyengaging and propelling the web at a location between said units, forsimultaneously and proportionally adjusting relative to the position andthe speed of said second unit both the length of the path and the speedof that lead of the web which extends from said driven roller means tosaid second unit so as to keep the web substantially constantly inregister with said second unit irrespective of the actual speed of saidunits, said register control means further including means for drivingsaid roller means in synchronism with said units, and

means for varying the speed of said roller means relative to the speedof said second unit;

register correction means including means for detecting a deviation ofsaid register points from registering relationship to said element onsaid second unit and means responsive to said detecting means foractuating said register control means to the extent and in the senserequired to correct such deviation;

and floating roller means yieldably biased against and positioned by andcounterbalancing the tension in the web lead to said driven roller meansfor maintaining said tension substantially constant.

2. A machine according to claim 1,

said floating roller means including a roller engaging and urged in onedirection by the pull of a portion of the web lead to said driven rollermeans and means urging said roller in an opposite direction with aconstant force so that the web tension in that lead is maintained at avalue proportional to said force, said machine further comprising,

web guiding idler rollers engaged and driven by said web lead betweensaid first unit and said driven roller means,

emergency control means for stopping the machine abruptly,

and means operative upon actuation of said energency control means todecrease said force and thereby the tension of said web lead to anextent suflicient to free said web guiding rollers from constraint bythe web so that they may coast to a stop without damaging the web.

3. A machine according to claim 1, said driven roller means beingdisplaceable in opposite directions longitudinally of said web path, andsaid actuating means including means for displacing said driven rollermeans in either of said directions and means for simultaneouslyadjusting said speed varying means by increments respectivelyproportional to the displacements of said driven roller means.

4. A machine according to claim 1, said register control means furtherincluding a displaceable idler roller at the downstream side of saiddriven roller means for positioning said web lead to said second unit,said idler roller being dispaceable in opposite directionslongitudinally of said web path, and said actuating means includingmeans for displacing said idler roller in either of said directions andfor simultaneously adjusting said speed varying means by incrementsrespectively proportional to the displacements of said idler roller.

5. In a multi-unit Web processing machine including a first set ofcoacting cylinders which impress a web at sucessive locations thereonand from which the web travels under tension through an extended path toa second set of coacting cylinders which impress the web at successivelocations to be maintained continually in register with the first saidlocations;

register control means, including driven rol-ler means non-slipablyengaging and propelling the web at a location between said sets ofcylinders, tor simultaneously and proportionally adjusting relative tothe position and the speed of said second set of cylinders both thelength of the path and the speed of that lead of the web which extendsfrom said driven roller means to said second set so as to keep theimpressions of the web substantially constantly in register irrespectiveof the actual speed of said cylinder sets, said register control meansfurther including means for driving said cylinder sets and said rollermeans in synchronism, and

means for varying the speed of said roller means relative to the speedof said second cylinder set,

register correction means including means for detecting a deviation ofthe first said locations from registering relationship to said secondset and means responsive to said detecting means for actuating saidregister control means to the extent and in the sense to correct suchdeviation,

and roller means yieldably biased against and positioned by andcounterbalancing the tension in the web lead to said driven roller meansfor maintaining said tension substantially constant.

6. A machine according to claim 5, including a clutch in the drivingtrain to said driven roller means,

a member adapted to clamp the web so as to prevent movement thereof butnormally held clear of the web,

and means operative upon disengagement of said clutch to move saidmember into web clamping position whereby to prevent rotation of thede-clutched roller means :by the web.

7. In a multi-unit web processing machine including a first set ofcoacting cylinders which imprint a web at successive locations thereonand from which the web travels through an extended path to a second setof coacting cylinders which imprint the web at successive locations tobe maintained continually in register with the first said locations,each set of said cylinders non-slippably gripping and propelling theweb;

coacting rollers engaging and for propelling the web in non-slippingrelation thereto in a part of said path near to said second set,

a carriage mounting said rollers and movable bodily to displace saidrollers in opposite directions longitudinally of the web path,

a carriage positioning means including a motor operative when actuatedto move said carriage and thereby said rollers bodily relative to saidfirst set of cylinders in either of said directions,

means for driving said cylinder sets and said rollers in synchronism,including a variable speed drive to said rollers the speed of which isvaried upon and in proportion to movement of said carriage in either ofsaid directions,

register corrections means including means for detecting a deviation ofsaid first locations from registering relationship to said second setand means responsive to said detecting means :for actuating said motorso as to move said carriage and simultaneously vary the speed of saidvariable speed drive to the extent and in the sense required to correctsuch deviation,

and a floating roller yieldably biased against and positioned by aportion of the web lead to said rollers for maintaining the tension inthat web lead substantially constant.

8. In a Web processing machine including a set of coacting cylinderswhich propel the Web and impress it at successive locations thereon andfrom which the web travels through an extended path to a further unit ofthe machine which propels the web and is driven in synchronism with saidcylinders, said cylinders being separable during stoppage periods of themachine and freeing the web so as to create slack in it when separated;

a floating idler roller engaging the web in said path and yieldablybiased against and positioned by the web for maintaining the tension ofthe web in said path substantially constant,

control means operative when actuated to stop the machine,

and means operative upon actuation of said control means to lock saidfloating roller in the position it then occupies to keep it fromdisplacing the web freed by said cylinders during the stoppage period.

9. In a web processing machine including a set of coacting cylinderswhich propel the web and impress it at successive locations thereon andfrom which the web travels through an extended path to a further stationof the machine with respect to which the impressed web is to be kept inregister, said cylinders being separable during stoppage periods of themachine and freeing the web so as to create slack in it when separated;

a driven roll means non-slippably engaging and propelling the web insaid path ahead of said station, means for driving said roller means insynchronism with said cylinders,

means operative upon said roller means for varying the speed of the Webportion engaged by said roller means relative to the speed of saidcylinders,

register correction means including means for detecting a deviation ofthe web from registering relationship to said station and meansresponsive to said detecting means for actuating said speed varyingmeans to the extent and in the sense required to correct such deviation,

a floating idler roller yieldably biased against and po sitioned by aportion of the web lead to said driven roller means for maintaining thetension in that web lead substantially constant.

control means operative when actuated to stop the machine,

and means operative upon actuation of said control means to latch saidfloating roller in the position it then occupies to keep it fromdisplacing the Web freed by said cylinders during the stoppage period.

10. In a multi-unit web processing machine including first and secondsets of coacting cylinders for impressing and propelling a web andbetween which the web travels through an extended path, and means fordriving said sets in synchronism, the second set impressing the web atsuccessive locations thereon which are to be maintained continually inregister with impressions formed by the first set;

driven roller means non-slippably engaging and propelling the Web in apart of said path near to said second set,

means for driving said roller means in synchronism with said sets,including means operative upon said roller means for varying the speedof the web portion en gaged by said roller means relative to the speedof the web portion engaged by said second set to vary the stretch of theweb lead extending from the roller means .to said second set,

register correction means including means for detecting a deviation ofsaid impressions from registering relationship to said second set andmeans responsive to said detecting means for actuating said speedvarying means in the sense required to correct such deviation,

a floating idler roller engaging and urged in one direction by the pullof a portion of the web lead to said driven roller means and meansurging said roller in an opposite direction with a constant force sothat the web tension in that lead is maintained substantially constant,

fixed web guiding idler rollers engaged and driven peripherally by saidweb lead between said first set and said driven roller means,

emergency control means operative when actuated to stop the machineabruptly,

service control means operative when actuated to stop the machinegradually,

means operative upon actuation of said emergency control means todecrease said force and thereby the tension of said web lead to anextent sufficient to free said fixed web guiding rollers from constraintby the web so that they may coast to a stop without damaging the web,

and means operative upon actuation of said service control means tolatch said floating roller in the position it then occupies to keep itfrom displacing the web.

11. In a web processing apparatus including successive rotary webprocessing units to act in register up a continuously moving web and afloating roller normally biased against and tensioning a lead of the webbetween said units;

a latchable element connected with said roller to move therewith,

a latching member movable into engagement with said element to preventdisplacement of said roller, said member normally being inactive,

means actuatable to press said member int-o engagement with said elementso as to hold said roller against displacement,

a fluid pressure cylinder having a piston connected with said roller tobias the same against said web lead,

a conduit for supplying fluid under pressure to said cylinder,

a control valve in said conduit having a first position in which thefluid pressure in said cylinder is at a relatively high value and asecond position in which said pressure is at least substantiallyreduced,

means continuously biasing said valve toward said second position,

means normally holding said valve in said first position against theforce of said biasing means,

and means operable selectively either to actuate said means to presssaid member into latching engage ment with said element or to inactivatesaid holding means, whereby either to latch said roller in the workingposition it then occupies or to reduce the fluid pressure acting upon itso as to prevent it from displacing said web lead.

12. A web processing machine including;

a rotary power source,

coacting rotary processing cylinders drivingly engaging the web innon-slipping relation thereto, said cylinders being separable duringstoppage periods of the machine and then freeing the web,

register control means, including driven rollers nonslippably engagingand propelling the web at a loca tion ahead of said cylinders, forsimultaneously and proportionally adjusting relative to the position andthe speed of said cylinders both the length of the path and the speed ofthat lead of the web which extends from said rollers to said cylindersso as to keep the web substantially constantly in register with saidcylinders irrespective of their actual speed, said register controlmeans further including means for driving said rollers and saidcylinders in synchronism from said power source, and

means for varying the ratio of the speed of said rollers to the speed ofsaid cylinders,

register correction means including means for detecting a deviation ofsaid web from registering relationship to said cylinders and meansresponsive to said detecting means for actuating said register controlmeans to the extent and in the sense required to correct such deviation,

means for continuing said cylinders in slow rotation by said powersource during stoppage periods of the machine while said cylinders areseparated from each other, 1

and a clutch in the driving train to said rollers whereby said rollersmay be disconnected from said source and the web held in place relativeto said cylinders during such stoppage.

13. In a web processing machine according to claim 12 wherein said powersource comprises a motor,

a primary power circuit to said motor,

a first control switch having a first position in which said primarymotor circuit is completed to supply power to the motor to energize thesame and a second position in which said circuit is broken,

an auxiliary power circuit completed upon movement of said first switchto said second position to maintain a supply of energizing power to saidmotor,

a second control switch efifective when actuated and with said firstswitch in said second position to break said auxiliary circuit,

and means rotating with said cylinders for actuating said second switchin a predetermined angular position of said cylinders, whereby saidcylinders are stopped in substantially the same angular position witheach stoppage of the machine and continue to be in register with the webwhen reengaged therewith following the stoppage period.

14. In a rotary web processing machine including a first set of coactingcylinders which imprint one side of a web at successive locationsthereon and from which the web travels under tension through an extendedpath to a second set of coacting cylinders which imprint the other sideof the web at successive locations to be maintained continually inregister with the first said locations, there being turn bars in saidpath for inverting the moving web;

register control means, including driven roller means non-slippablyengaging and propelling the inverted web at a location between said turnbars and said second set of cylinders, for simultaneously andproportionally adjusting relative to the position and the speed of saidsecond set of cylinders both the length of the path and the speed ofthat lead of the inverted web which extends from said roller means tosaid second set so as to keep the successive imprints on the websubstantially constantly in register irrespective of the actual speed ofsaid cylinder sets, said register control means further including meansfor driving said cylinder sets and said roller means in synchronism, and

means for varying the speed of said roller means relative to the speedof said second set;

register correction means including means for detecting a deviation ofthe first said locations from registering relationship to said secondset and means responsive to said detecting means for actuating saidregister control means to he extent and in the sense to correct suchdeviation;

and floating roller means yieldably biased against and positioned by andcounterbalancing the tension in the web about to enter said turn barsfrom maintaining substantially constant tension in the respective websection approaching and on the turn bars and extending from them to saiddriven roller means.

15. In a rotary web processing machine including a first set of coactingcylinders which imprint one side of a web at successive locationsthereon and from which the web travels under tension through an extendedpath to a second set of coacting cylinders which imprint the other sideof the web at successive locations to be maintained continually inregister with the first said locations, there being turn bars in saidpath for inverting the moving web;

register control means, including driven roller means non-slippablyengaging and propelling the inverted web at a location between said turnbars and said second set of cylinders, for simultaneously andproportionally adjusting relative to the position and the speed of saidsecond set of cylinders both the length of the path and the speed ofthat lead of the inverted web which extends from said roller means tosaid second set so as to keep the successive imprints on the websubstantially constant in register irrespective of the actual speed ofsaid cylinder sets, said register control means further including meansfor driving said cylinder sets and said roller means in synchronism, and

means for varying the speed of said roller means relative to the speedof said second set;

register correction means including means for detecting a deviation ofthe first said locations from regis tering relationship to said secondset and means responsive to said detecting means for actuating saidregister control means to the extent and in the sense to correct suchdeviation;

floating roller means yieldably biased against and positioned by andcounterbalancing the tension in the inverted web between said turn barsand said driven roller means for maintaining substantially constanttension in web sections on the turn bars and beyond them to said drivenroller means,

and variable speed, driven tension control means acting upon the webahead of said turn bars to propel and to maintain substantially constanttension in the web lead from said first set of cylinders and to limitthe tension level of the web section moving onto the turn bars, saidtension control means being driven in synchronism with said cylindersets and said driven roller means and being responsive to variations ofthe tension of the web traveling thereto to vary the speed of propulsionof the same in compensation for such tension variations.

16. A machine as defined in claim 15, further including variable speed,driven tension control means acting upon the web in the web loop betweensaid turn bars to propel and to maintain substantially constant tensionin the web at the first turn bar and to limit the tension level of theweb section moving onto the second turn bar, said tension control meansbeing driven in synchronism with said cylinder sets and said drivenroller means and being responsive to variation of the tension of the webtraveling thereto to vary the speed of propulsion of the same incompensation for such tension variations.

17. In a rotary web processing machine including a first set of coactingcylinders which imprint one side of a web at successive locationsthereon and from which the web travels under tension through an extendedpath to a second set of coacting cylinders which imprint the other sideof the web at successive locations to be maintained continually inregister with the first said locations, there being turn bars in saidpath for inverting the moving web;

register control means, including driven roller means non-slippablyengaging and propelling the inverted web at a location between said turnbars and said second set of cylinders, for simultaneously and proportionally adjusting relative to the position and the speed of saidsecond set of cylinders both the length of the path and the speed ofthat lead of the inverted web which extends from said roller means tosaid second set so as to keep the successive imprints on the websubstantially constantly in register irrespective of the actual speed ofsaid cylinder sets, said register control means further including meansfor driving said cylinder sets and said roller means in synchronism, and

means for varying the speed of said roller means relative to the speedof said second set,

register correction means including means for detecting a deviation ofthe first said locations from registering relationship to said secondset and means responsive to said detecting means for actuating saidregister control means to the extent and in the sense to correct suchdeviation,

floating roller means yieldably biased against and positioned by andcounterbalancing the tension in the inverted web between said turn barsand said driven roller means for maintaining substantially constanttension in web sections at the turn bars and beyond them to said drivenroller means,

and variable speed, driven tension control means acting upon the web inthe web loop between said turn bars to propel and to maintainsubstantially constant tension in the web at the first turn bar and tolimit tension level of the web section moving onto the second turn bar,said tension control means being driven in synchronism with saidcylinder sets and said driven roller means and being, responsive tovariations of the tension of the Web traveling thereto to vary the speedof propulsion of the same in compensation for such tension variations,

18. In a Web processing machine including a rotary unit for processingin register a Web traveling continuously thereto,

driven roller means non-slippably engaging and propelling the web leadto said unit,

an idler roller engaging said web lead at the downstream side of saiddriven roller means, said idler roller being displa-ceable to vary theposition of said Web lead relative to said unit, means including avariable speed drive driven in synchronism with said unit for drivingsaid roller means, said drive including an endless belt, meanspositioned and displaced with said idler roller for tensioning saidbelt, and means responsive to variations of the tension of said belt tovary correspondingly the ratio of the speed of said roller means to thespeed of said unit, means for sensing deviations of the traveling webfrom registered relation to said unit and for generating signalsproportional to the sensed register errors,

and means responsive to said signal to displace said idl'er roller andsaid belt tensioning means correspondingly so as to vary simultaneouslythe relative position of said Web lead and the speed thereof relative tothe speed of said unit in the sense to correct the register errors.

References Cited by the Examiner UNITED STATES PATENTS 1,245,410 11/1917Walkup 101-228 2,106,338 1/1938 Black 226-13 2,263,323 11/1941 Wickwire101-182 2,281,900 5/1942 Wieking 101-180 X 2,469,283 5/ 1949 Steele292-201 2,500,230 3/1950 Bailey et al. 226-30 X 2,549,605 4/1951 Huck226-30 X 2,645,174 7/1953 Levin 101-132 2,699,937 1/1955 KOtte 226-602,700,447 1/1955 Bloggett 197-20 2,884,856 5/1959 Brodie 226-41 X2,897,754 8/1959 Spiller et al 101-180 2,949,295 8/1960 Huck 226-3,093,069 6/1963 Lu'ehrs 101-179 3,097,844 7/1963 Huck 226-30 X FOREIGNPATENTS 416,104 9/ 19-34 Great Britain.

ROBERT E. PULFREY, Primary Examiner.

J. R. FISHER, Assistant Examiner.

1. IN A MULTI-UNIT WEB PROCESSING MACHINE INCLUDING FIRST AND SECONDROTARY PROCESSING UNITS FOR ENGAGING AND PROPELLING A WEB AND BETWEENWHICH THE WEB TRAVELS UNDER TENSION THROUGH AN EXTENDED PATH, AND MEANSFOR DRIVING SAID UNITS IN SYNCHRONISM, EACH OF SAID UNITS NORMALLYHOLDING THE WEB IN NON-SLIPPING RELATION THERETO, SAID FIRST UNIT HAVINGAN ELEMENT THEREON THAT REGISTERS CYCLICALLY WITH SUCCESSIVE POINTS ONTHE WEB WHICH ARE TO BE MAINTAINED CONTINUALLY IN REGISTER WITH ANELEMENT ON SAID SECOND UNIT; REGISTER CONTROL MEANS, INCLUDING DRIVENROLLER MEANS NON-SLIPPABLY ENGAGING AND PROPELLING THE WEB AT A LOCATIONBETWEEN SAID UNITS, FOR SIMULTANEOUSLY AND PROPORTIONALLY ADJUSTINGRELATIVE TO THE POSITION AND THE SPEED OF SAID SECOND UNIT BOTH THELENGTH OF THE PATH AND THE SPEED OF THAT LEAD OF THE WEB WHICH EXTENDSFROM SAID DRIVEN ROLLER MEANS TO SAID SECOND UNITS SO AS TO KEEP THE WEBSUBSTANTIALLY CONSTANTLY IN REGISTER WITH SAID SECOND UNIT IRRESPECTIVEOF THE ACTUAL SPEED OF SAID UNITS, SAID REGISTER CONTROL MEANS FURTHERINCLUDING MEANS FOR DRIVING SAID ROLLER MEANS IN SYNCHRONISM WITH SAIDUNITS, AND MEANS FOR VARYING THE SPEED OF SAID ROLLER MEANS RELATIVE TOTHE SPEED OF SAID SECOND UNIT; REGISTER CORRECTION MEANS INCLUDING MEANSFOR DETECTING A DEVIATION OF SAID REGISTER POINTS FROM REGISTERINGRELATIONSHIP TO SAID ELEMENT ON SAID SECOND UNIT AND MEANS RESPONSIVE TOSAID DETECTING MEANS FOR ACTUATING SAID REGISTER CONTROL MEANS TO THEEXTENT AND IN THE SENSE REQUIRED TO CORRECT SUCH DEVIATION; AND FLOATINGROLLER MEANS YIELDABLY BIASED AGAINST AND POSITIONED BY ANDCOUNTERBALANCING THE TENSION IN THE WEB LEAD TO SAID DRIVEN ROLLER MEANSFOR MAINTAINING SAID TENSION SUBSTANTIALLY CONSTANT.